The invention relates to a composite conductor rail, in particular a high-performance railway conductor rail having an aluminum base-section and, as contact surface for the power collector, at least one steel strip.
For those cases where overhead or open line power supplies do not come into question for supplying electric power to electric trains, cabin-taxis, travelling cranes and the like, it is known to make use of conductor rails. The large weight of a conductor rail made solely of steel can be reduced to about 1/7 by a combined aluminum-steel conductor rail, at the same time maintaining the same electrical conductivity.
The following manufacturing methods have been employed up to now on an industrial scale:
Coextrusion of an aluminum section with a steel strip PA0 Bolting aluminum plates onto the sides of a steel section PA0 Clamping a U-shaped steel sheet onto an aluminum section PA0 Casting aluminum into the sides of a steel I-beam.
Of these methods coextrusion is particularly advantageous as it produces a metallic bond between the steel and the aluminum. This connection not only ensures an optimal transfer of current, but also prevents any crevice corrosion in the region of transition between the two metals.
Although coextruded conductor rails exhibit considerable advantages over other versions, their unlimited economic application, in particular in high-performance railway conductor rails, is narrowed down by a plurality of parameters such as for example the maximum possible outer dimensions, extrusion speed and in the case of hollow sections by the wall thickness. Using the present state of the art it is possible to produce coextruded steel-aluminum conductor rails only up to a weight per running meter of at most about 18 kg and a section height of at most about 130 mm.
Today, however, conductor rails with larger dimensions are sometimes necessary, in particular for electric railways; such rails cannot be made or cannot be made economically by the basically advantageous coextrusion method with the present-day means.
The object of the present invention is therefore to develop a composite conductor rail as discussed above, which is not limited in height or weight of extrusion by extrusion parameters and provides therefore any desired power-carrying capacity, in particular also in excess of 4700A. This conductor rail should exhibit a mechanical strength capable of withstanding the vibrational stressing and temperature changes in the rough conditions of a rail transportation system both in tunnels and in the open air, and this for a period of 30-50 years. Furthermore, the conductor rail should as a whole ensure good current transfer, be universally applicable and economic to manufacture.